Diabetes occurs when the body has trouble using the sugar it gets from food for energy. Sugar builds up in the bloodstream. High blood sugar can have immediate effects, like blurry vision. It can also cause problems over time, like heart disease and blindness.

There are two main types of diabetes: type 1 diabetes (once called juvenile-onset diabetes) and type 2 diabetes (once called adult-onset diabetes). Both are caused by problems making or using insulin, a hormone that makes it possible for cells to use glucose, also known as blood sugar, for energy.

When you eat, your body breaks down carbohydrates into a simple sugar called glucose. It also produces a hormone called insulin that signals the body's cells to absorb glucose from the bloodstream. Type 1 diabetes occurs when the body doesn't make enough insulin, or stops making it altogether. Type 2 diabetes occurs when the body's cells don't respond to insulin. Either way, since sugar can't get into cells, it builds up in the bloodstream. 

Too much sugar in the blood can cause a range of uncomfortable symptoms. These include:

  • blurry vision
  • intense thirst
  • need to urinate often
  • fatigue
  • numbness or tingling in the hands or feet

Type 1 diabetes often comes on suddenly. It usually strikes children and teenagers, but can appear later in life. It is an autoimmune disease, meaning it happens because the body's immune system mistakenly attacks and destroys the body's insulin-making cells. Type 1 diabetes can't be cured, but it can be managed by taking insulin before eating.

Type 2 diabetes takes longer to develop. It can begin any time from childhood onward. Type 2 diabetes is usually triggered by being overweight or obese and not getting much physical activity. Treatment for type 2 diabetes includes weight loss if needed, daily exercise, a healthy diet, and medications.

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Healthy gut, healthy heart?

The gut microbiome refers to the genes that govern the trillions of microbes in the human intestinal tract. These bacteria and other microbes make an array of substances that influence the body’s vascular, nervous, endocrine, and immune systems. These substances play a role in regulating blood pressure and blood sugar and the formation of artery-clogging plaque (atherosclerosis). Dietary habits that are helpful for preventing heart disease—such as avoiding red meat, keeping salt intake low, and eating lots of fiber-rich vegetables and whole grains—also have favorable effects on the gut microbiome. More »

Hidden risk factors that could put your heart in danger

Women who had gestational diabetes or pre-eclampsia during pregnancy have a higher risk of developing cardiovascular disease later in life. As a result, they should take prevention seriously and be aggressive about lifestyle interventions. (Locked) More »

Deterring heart disease if you have diabetes

Three newer medications for type 2 diabetes, empagliflozin (Jardiance), canagliflozin (Invokana) and liraglutide (Victoza), appear to lower the risk of dying of cardiovascular disease in addition to lowering blood sugar. Empagliflozin and canagliflozin, which improve diabetes by helping the body release more sugar into the urine, seem to be especially helpful for decreasing heart failure cases. Liraglutide lowers blood sugar by preventing the liver from making too much sugar and helping the pancreas produce more insulin. It reduced serious heart events by 13% and deaths from heart disease by 22%. People with type 2 diabetes and heart disease who are having trouble reaching their HbA1c targets may want to discuss these new medications with their doctors. (Locked) More »

Midlife heart health shows a link with future risk of dementia

People who have high blood pressure and diabetes and who smoke during middle age have a higher risk of heart attack and stroke. These vascular (blood vessel) risk factors may leave them more prone to dementia 25 years later. Having diabetes in middle age may be almost as risky as having the gene variant known as APOE4, which is associated with an increased risk of Alzheimer’s disease, the most common form of dementia. Even slightly elevated blood pressure during midlife may be associated with dementia in later life. (Locked) More »

Test may someday help predict diabetes risk

A new test called lipoprotein insulin resistance may more accurately predict whether a woman will develop type 2 diabetes than existing methods of assessing risk, such as family history of the disease, body mass index, and blood glucose levels. The test can pick up on signs of insulin resistance, which can lead to diabetes, before a woman has an abnormal glucose test. (Locked) More »